arm64: ptrace: remove addr_limit manipulation

[ Upstream commit 59275a0c03 ]

We transiently switch to KERNEL_DS in compat_ptrace_gethbpregs() and
compat_ptrace_sethbpregs(), but in either case this is pointless as we
don't perform any uaccess during this window.

let's rip out the redundant addr_limit manipulation.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mark Rutland 2018-04-24 13:11:22 +01:00 committed by Greg Kroah-Hartman
parent ef0fa5e6f5
commit e6ec885f5f

View file

@ -1194,9 +1194,7 @@ static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
{
int ret;
u32 kdata;
mm_segment_t old_fs = get_fs();
set_fs(KERNEL_DS);
/* Watchpoint */
if (num < 0) {
ret = compat_ptrace_hbp_get(NT_ARM_HW_WATCH, tsk, num, &kdata);
@ -1207,7 +1205,6 @@ static int compat_ptrace_gethbpregs(struct task_struct *tsk, compat_long_t num,
} else {
ret = compat_ptrace_hbp_get(NT_ARM_HW_BREAK, tsk, num, &kdata);
}
set_fs(old_fs);
if (!ret)
ret = put_user(kdata, data);
@ -1220,7 +1217,6 @@ static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
{
int ret;
u32 kdata = 0;
mm_segment_t old_fs = get_fs();
if (num == 0)
return 0;
@ -1229,12 +1225,10 @@ static int compat_ptrace_sethbpregs(struct task_struct *tsk, compat_long_t num,
if (ret)
return ret;
set_fs(KERNEL_DS);
if (num < 0)
ret = compat_ptrace_hbp_set(NT_ARM_HW_WATCH, tsk, num, &kdata);
else
ret = compat_ptrace_hbp_set(NT_ARM_HW_BREAK, tsk, num, &kdata);
set_fs(old_fs);
return ret;
}